Former University of Hong Kong vice-chancellor Professor Tsui Lap-chee and ex-financial secretary Antony Leung Kam-chung were among the standout names among 39 moderates from both sides of the political divide who signed a petition calling for consensus on political reform.

The signatories warn that "confrontational sentiments and behaviour have escalated to worrying levels" amid a debate over the 2017 chief executive election. They say the situation can only get worse if efforts to introduce universal suffrage fail.

"Intransigency stymies negotiation, polarises society and bring chaos," said Andrew Fung Ho-keung, coordinator of the petition drive and chief executive of the Policy Research Institute. He urged all parties to negotiate and consider all "practicable" plans for reform.

The Standing Committee of the National People's Congress is widely expected to give Hong Kong the green light for reform this month, while setting a framework for a second round of public consultation later this year. But the vexed question of how candidates will be nominated has cast doubt on whether a reform plan will win the required two-thirds majority in the legislature.

Fung stressed that the group was not advocating any particular reform model, nor pointing the finger at supporters or opponents of Occupy Central's plans for civil disobedience.

Other prominent signatories include Legislative Council president Jasper Tsang Yok-sing, Federation of Trade Unions lawmaker Chan Yuen-han and NPC delegate Priscilla Lau Pui-king. Chan said she hoped all parties would work to create an atmosphere conducive to dialogue.

Leung, occasionally tipped as a candidate in 2017, has largely stayed out of politics since resigning in 2003. Tsui also stayed out of the democracy debate in his 12 years at the helm of HKU.

Democratic Party founding member Dr Law Chi-kwong, HKU law lecturer Eric Cheung Tat-ming and Stanley Ng Wing-fai, vice-chairman of pro-democracy group Professional Commons, have also signed.

Law said pan-democrats might be reluctant to sign for fear of being branded too willing to compromise. His party's executive was expected to discuss the petition last night.